Create base-css-class button-group

Change-Id: I05afa3885c505ec59a555710c935016de396be26
diff --git a/dev/scss/base.scss b/dev/scss/base.scss
index 99fe4c8..5404508 100644
--- a/dev/scss/base.scss
+++ b/dev/scss/base.scss
@@ -135,3 +135,35 @@
 button + button {
   right: 0;
 }
+
+
+.button-group {
+  > span {
+    cursor: pointer;
+    box-shadow: $choose-box-shadow;
+    font-size: 9pt;
+    line-height: 1.5em;
+    padding: 0 4px;
+    display: inline-block;
+    @include choose-item;
+    border-style: solid;
+    border-width: $border-size 0;
+    &:hover {
+	    @include choose-hover;
+    }
+    &:first-child {
+	    border: {
+	    left-width: $border-size;
+	    top-left-radius: $standard-border-radius;
+	    bottom-left-radius: $standard-border-radius;
+	  }
+    }
+    &:last-child {
+	    border: {
+	    right-width: $border-size;
+	    top-right-radius: $standard-border-radius;
+	    bottom-right-radius: $standard-border-radius;
+	  }
+    }
+  }
+}
\ No newline at end of file